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Photoassociation Spectroscopy of Ultracold Atoms and the Study of Physicists' Molecules



Kevin Jones, Eite Tiesinga, Paul D. Lett, Paul S. Julienne


Photoassociation is the process where two colliding atoms absorb a photon to form an excited molecule. The development of laser cooling techniques for producing gasses at ultracold (< 1 mK) temperatures has allowed photoassociation spectroscopy to be performed with very high spectralresolution. In particular, it has allowed the probing of purely long range molecular states and the investigation of such physicist s molecules, - molecules whose properties can be derived with high precision from the properties of their constituent atoms. This review describes what is special about photoassociation spectroscopy at ultracold temperatures, how it is performed, andhow it is used to investigate cold atomic collisions and extract atomic and molecular properties. We discuss the extraction of scattering lengths, their control via optical Feshbach resonances, precision determinations of atomic lifetimes, rate limits in a Bose-Einstein condensate, and briefly, production of cold molecules. Discussions are illustrated with examples on alkali-metal atoms aswell as other species. Progress in the field is already past the point where this review can be exhaustive, but we offer an introduction to the capabilities of photoassociation spectroscopy and to the techniques presently in use.
Reviews of Modern Physics


atomic collisions, diatomic molecules, laser cooling, photoassociation, photoionization, scattering lengths, spectroscopy


Jones, K. , Tiesinga, E. , Lett, P. and Julienne, P. (2006), Photoassociation Spectroscopy of Ultracold Atoms and the Study of Physicists' Molecules, Reviews of Modern Physics (Accessed July 22, 2024)


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Created May 21, 2006, Updated October 12, 2021